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Neumaier Thermal Interpretation of QM, valid? 
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#1
Apr1511, 09:02 PM

P: 275

For those of us trapped in a corner with difficult choices of whether to believe many worlds are splitted off billions of times every second or whether there is Godlike power to collapse the wave function in the universe or whether waves can travel forward or backward in time (Transactional) or wave function that is instantaneous from end to end of the entire universe (Bohmian), etc. Neumaire Thermal Interpretation of Quantum Mechanics may offer us peace of mind and contentment that the mystery of quantum mechanics is solved. But the question is, is Neumaire Thermal Interpretation valid or tally with all experimental facts? If you have detected any conflict with experiments that can falsify his model, pls share it. If it's valid, maybe someone can put it at wikipedia. Neumaire can you pls create a more layman friendly introduction to it like describing in detail how it explains buckyball made up of 430 atoms that can still interfere with itself? I cant understand the vague abd incomplete explanation you put forth in your paper. Thanks.
Arnold Neumaire said: " I have my own interpretation. I call it the the thermal interpretation since it agrees with how one does measurements in thermodynamics (the macroscopic part of QM (derived via statistical mechanics), and therefore explains naturally the classical properties of our quantum world. It is outlined in my slides at http://www.mat.univie.ac.at/~neum/ms/optslides.pdf and the entry ''Foundations independent of measurements'' of Chapter A4 of my theoretical physics FAQ at http://www.mat.univie.ac.at/~neum/ph...aq.html#found0 . It is described in detail in Chapter 7 of my book ''Classical and Quantum Mechanics via Lie algebras'' at http://lanl.arxiv.org/abs/0810.1019 . See also the following PF posts: http://www.physicsforums.com/showthr...al#post3187039 http://www.physicsforums.com/showthr...al#post3193747 The thermal interpretation It is superior to any I found in the literature, since it  acknowledges that there is only one world,  is observerindependent and hence free from subjective elements,  satisfies the principles of locality and Poincare invariance, as defined in relativistic quantum field theory,  is by design compatible with the classical ontology of ordinary thermodynamics  has no split between classical and quantum mechanics,  applies both to single quantum objects (like a quantum dot, the sun or the universe) and to statistical ensembles,  allows to derive Born's rule in the limit of a perfect vonNeumann measurement (the only case where Born's rule has empirical content),  has no collapse (except approximately in nonisolated subsystems).  uses no concepts beyond what is taught in every quantum mechanics course, No other interpretation combines these merits. The thermal interpretation leads to a gain in clarity of thought, which results in saving a lot of time otherwise spent in the contemplation of meaningless or irrelevant aspects arising in poor interpretations. The thermal interpretation is based on the observation that quantum mechanics does much more than predict probabilities for the possible results of experiments done by Alice and Bob. In particular, it quantitatively predicts the whole of classical thermodynamics. For example, it is used to predict the color of molecules, their response to external electromagnetic fields, the behavior of material made of these molecules under changes of pressure or temperature, the production of energy from nuclear reactions, the behavior of transistors in the chips on which your computer runs, and a lot more. The thermal interpretation therefore takes as its ontological basis the states occurring in the statistical mechanics for describing thermodynamics (Gibbs states) rather than the pure states figuring in a quantum mechanics built on top of the concept of a wave function. This has the advantage that the complete state of a system completely and deterministically determines the complete state of every subsystem  a basic requirement that a sound, observerindependent interpretation of quantum mechanics should satisfy. The axioms for the formal core of quantum mechanics are those specified in the entry ''Postulates for the formal core of quantum mechanics'' of Chapter A4 of my theoretical physics FAQ at http://www.mat.univie.ac.at/~neum/ph...tml#postulates . There only the minimal statistical interpretation agreed by everyone is discussed. The thermal interpretation goes far beyond that, assigning states and an interpretation for them to individual quantum systems, in a way that large quantum systems are naturally described by essentially classical observables (without the need to invoke decoherence or collapse). The new approach is consistent with assigning a welldefined (though largely unknown) state to the whole universe, whose properties account for everythng observable within this universe. The fundamental mathematical description of reality is taken to be standard quantum field theory. It doesn't matter for the thermal interpretation whether or not there is a deeper underlying deterministic level. In my thermal interpretation of quantum physics, the directly observable (and hence obviously ''real'') features of a macroscopic system are the expectation values of the most important fields Phi(x,t) at position x and time t, as they are described by statistical thermodynamics. If it were not so, thermodynamics would not provide the good macroscopic description it does. However, the expectation values have only a limited accuracy; as discovered by Heisenberg, quantum mechanics predicts its own uncertainty. This means that <Phi(x)> is objectively real only to an accuracy of order 1/sqrt(V) where V is the volume occupied by the mesoscopic cell containing x, assumed to be homogeneous and in local equilibrium. This is the standard assumption for deriving from first principles hydrodynamical equations and the like. It means that the interpretation of a field gets more fuzzy as one decreases the size of the coarse graining  until at some point the local equilibrium hypothesis is no longer valid. This defines the surface ontology of the thermal interpretation. There is also a deeper ontology concerning the reality of inferred entities  the thermal interpretation declares as real but not directly observable any expectation <A(x,t)> of operators with a spacetime dependence that satisfy Poincare invariance and causal commutation relations. These are distributions that produce measurable numbers when integrated over sufficiently smooth localized test functions. Deterministic chaos is an emergent feature of the thermal interpretation of quantum mechanics, obtained in a suitable approximation. Approximating a multiparticle system in a semiclassical way (mean field theory or a little beyond) gives an approximate deterministic system governing the dynamics of these expectations. This system is highly chaotic at high resolution. This chaoticity seems enough to enforce the probabilistic nature of the measurement apparatus. Neither an underlying exact deterministic dynamics nor an explicit dynamical collapse needs to be postulated. The same system can be studied at different levels of resolution. When we model a dynamical system classically at high enough resolution, it must be modeled stochastically since the quantum uncertainties must be taken into account. But at a lower resolution, one can often neglect the stochastic part and the system becomes deterministic. If it were not so, we could not use any deterministic model at all in physics but we often do, with excellent success. This also holds when the resulting deterministic system is chaotic. Indeed, all deterministic chaotic systems studied in practice are approximate only, because of quantum mechanics. If it were not so, we could not use any chaotic model at all in physics but we often do, with excellent success.[/QUOTE] 


#2
Apr1611, 02:45 AM

P: 275

One major idea being put forth by Neumaire is that fields are now primary and particles are just momentum of the fields. So particle concept is now outdated and there is no sense of thinking of the double slit experiment as particle that moves in between the emitter and detector but more like field interacting in between (perhaps like Feynmann interaction vortexes). If that is true, then the buckyball composing of 430 atoms can be considered as field too.. but does it make sense to think in terms of 430 atom buckyball field??



#3
Apr1611, 02:57 PM

P: 661

A Neumaier is clearly a very erudite and impressive scholar, but his interpretation is unlikely to be correct as modern experiments urge a fundamental probabilistic character to Nature which his interpretation is not in agreement with. I doubt he can explain all the results of Zeilinger, Aspect et al in a very coherent manner.
He is a genius clinging to old school deterministic ideas about nature a la Einstein, but no amount of obfuscating the microscopic nature of reality will make its fundamental probabilistic nature go away. And also I'm not sure he should be allowed to promote such a non peer reviewed philosophy so strongly on these forums. His upcoming book has excellent sections on lie groups and their applications, but the interpretation stuff is really not scientific, and his excellence in many science and mathematical areas should not be confused with correct understanding of the deep implications of quantum theory. 


#4
Apr1611, 06:42 PM

P: 275

Neumaier Thermal Interpretation of QM, valid?
http://arxiv.org/abs/quantph/0212095 which says: "Contrary to common belief, it is not difficult to construct deterministic models where stochastic behavior is correctly described by quantum mechanical amplitudes, in precise accordance with the CopenhagenBohrBohm doctrine" So Neumaire approach where randomness is not fundamental is not reputed. What makes Neumaire approach possibly valid is that it needs no new assumptions but by just being updated... it looks like all those interpretations used the old concept of particles. We know that field is primary and particles just momentum of it. So if we look the double slit experiment with new updated point of view, perhaps it explains everything? Or is there subtle differences that can refute Neumaier idea? Again don't go to the reason being random probability is fundamental because one of the leading theoretical physicists has given reasons it is not and determinism may be more fundamental. See the famous paper above. In this very drastic hours where the public are being convinced Many Worlds may be the logical option left. Neumaire approach means going back to sanity and I think it's valid. Arnold, can you please write a Wikipedia article about it and give the basics as your articles are so vague and disorganized. The thermal approach may let us go back to sanity in this crazy world. 


#5
Apr1611, 08:01 PM

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P: 1,940

Anyway, the thing about interpretations is that if you can't find an experiment that distinguishes between them quantitatively, then the only guiding principle left is Occam's razor. Independent Research forum, but perhaps that will take a while to pass moderation given the size of the book. Let us remain patient and polite until then. BTW, (rodsika), while waiting, you might be interested to read Ballentine's articles on the statistical interpretation of QM (for which I given references earlier) if you haven't already done so. I've found it helpful to be aware of this simpler (but related) perspective when reading Arnold's book. 


#6
Apr1611, 08:30 PM

P: 239

Neumaier gives example of beam of photon. But a beam of photon has real wave, whereas electron wave is just probability wave. So one can't argue whether before observation, a beam of photon is there or not. It has real wave. Whereas matter waves are not actual waves. There goes my first attempt to refute his interpretation.
I have a question. Feynman mentions in his book "The Strange Story of Light and Matter" about reflections of light. He said that in reflections in a glass, 4% of the photons are always deflected. How do the photons know how to be 4% Feynmann asks. What I want to know is, can reflections be done with matter wave too like electron wave such that you can also see 4% of electron being deflected? 


#7
Apr1611, 09:37 PM

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#8
Apr1711, 01:27 AM

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Enlarge your picture of "expectation values" to include variance and higher moments of a probability distribution. E.g., for a quantity "A", its mean in a given state is of the form [tex]\bar{A} = \langle A \rangle[/tex], while its variance is of the form [tex]var(A) = \langle (A  \bar{A})^2\rangle[/tex]. I.e., the quantity [tex](A  \bar{A})^2[/tex] is just as valid an element of the algebra of observable quantities as A, for the class of system being considered. If var(A) is very small, we can think of the system in that state as having an "almost" definite value <A> corresponding to the quantity A. 


#9
Apr1711, 03:07 AM

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#10
Apr1711, 12:34 PM

P: 661

And I have looked through the draft of his book, maybe the final version will clarify some ideas. 


#11
Apr1711, 09:48 PM

P: 239

Do you guys agree that the Ensemble Interpretation (a requirement for Neumaier Interpretation) is already falsified? It is said at the bottom of http://en.wikipedia.org/wiki/Ensemble_Interpretation that
"However, hopes for turning quantum mechanics back into a classical theory were dashed. Gribbin continues: "There are many difficulties with the idea, but the killer blow was struck when individual quantum entities such as photons were observed behaving in experiments in line with the quantum wave function description. The Ensemble interpretation is now only of historical interest."[11]"" I presume that the Ensemble Interpretation is the same as the Statistical Interpretation? Both these can't handle single system. But Neumaier Interpretation (actually not an Interpretation but just a QFT way of looking at it or from a QFT point of view) can handle single system. Why is that Neumaier's can handle single system while the Ensemble and Statistical can't since they are identical? What are the differences? If we can refute Neumaier. Then we can eliminate all statistical interpretations and maybe focus and accept in Many Worlds or Bohmian. 


#12
Apr1711, 11:30 PM

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like to think of individual events in experiments as definite outcomes, all experiments involve some level of statistical analysis. No one trusts an isolated event as being reliable, without many more similar events to make it statistically significant. In an experiment, we arrange for an interaction between an object system in some state S and an apparatus (whose initial state A is initially uncorrelated with S) results in a new state A' of the apparatus for which there's a correlation between A' and S, if the experiment is performed enough times. If the variance of such apparatus poststates A' is very small, we interpret S as a deterministic (definite) state for the observable quantity represented by the apparatus. calculate expectation values, variances, covariances, correlations, etc, interpreted over an ensemble. "definite" or "deterministic" value of the observable quantity represented by A. Nevertheless, we can still report something useful in the form of an observed probability distribution. (BTW, I prefer the "deterministic" over "definite" since it conveys a more useful meaning.) informal anecdotal stories) suggests the contrary. 


#13
Apr1811, 12:14 AM

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incorrect results? References? (Personally, I find minimizing interpretational baggage as much as possible to be quite attractive.) 


#14
Apr1811, 12:18 AM

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Think of it this way: suppose you want to build a simulated universe running on a computer (or collection of computers, see below), and the simulation is supposed to model all the types of macrostates we can directly observe (while it doesn't need to have any model of microstates which we only infer based on macrostates). The model need not predict the results of particular trials of any realworld experiment, but we should be able to create a model of the same type of experiment on our computer(s), with the simulation yielding a series of macroscopic pointer states whose overall statistics should match the results of analogous experiments performed in the real world. If we require that the simulation be a "local" one, then we could imagine a bunch of computers which were each responsible for simulating a small element of space, and on each timeincrement the computer should give an output based only on inputs from other computer outputs that lie within its past light cone (this is assuming the laws of physics can be approximated arbitrarily well be a simulation with discrete "pixels" of space and time; if not, you could imagine replacing the finite array of computers with a perfectly continuous array of "functions" at each point in space, which continuously produce outputs at each instant of time based only on inputs from points in their past light cone). And the computers can have stochastic random number generators built in, so if part of their output consisted of a probability distribution, they could also use that probability distribution to randomly select one specific output based on that distribution. If observable macrostates in a region of space at a particular time are just a function of all the computers' outputs in that region at that time (outputs which may be thought of as "microstates" for specific points in space), then the point here is that no "local" simulation of this type, where the computers have no access to inputs outside their past light cone when generating outputs, can ever give a pattern of macrostates consistent with QM. Even if computers at each point can generate probability distributions in a local way, a stochastic rule for generating specific outcomes based on these probability distributions would have to operate nonlocally, with computers representing points at a spacelike separation coordinate their random choices to make sure they created the correct entanglement correlations. This is just a natural consequence of Bell's theorem. So, I think it's misleading to call Neumaier's interpretion a "local" one, it either fails to model the fact that we see particular outcomes for macroscopic pointer states (which all other interpretations attempt to account for) rather than just probability distributions, or if the model is made to include a stochastic rule for generating a series of particular macrostates, then the rule must operate in a nonlocal fashion. 


#15
Apr1811, 12:29 AM

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not classical, and the kind of probability that occurs in quantum theory is not exactly the same as classical  because noncommuting quantities cause difficulty with the probability axiom concerning "A and B" types of events. But that's a different issue. BTW, that part of the Wikipedia page quoting Gribbin is not supported by peerreviewed references, but only a link to Gribbin's Wiki page mentioning his early training in astrophysics, and his career as a science writer. To say that "the Ensemble interpretation is now only of historical interest" is inaccurate. 


#16
Apr1811, 12:36 AM

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#17
Apr1811, 06:03 AM

P: 661

R Omnes  'Consistent Interpretations of Quantum Mechanics' Rev Mod Phy Vol 64 No 2 1992 p339383 http://rmp.aps.org/abstract/RMP/v64/i2/p339_1 (pdf 44 pages ~9mb) However, I can't find the relevant paragraph, so I might be thinking of another paper. But in any case, the minimal statistical interpretation says so little beyond what the basic mathematical shut up and calculate method says that I'm not sure it can be regarded as an interpretation at all. 


#18
Apr1811, 08:29 PM

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I'm concerned about one aspect of the "statistical interpretation". It appears that most people take it to be defined by Ballentine's 1970 article, which I haven't read myself. The reason why I'm concerned is that the quotes I've seen seem to contradict Bell's theorem. This is from section 4.4 of "Ensemble interpretations of quantum mechanics. A modern perspective", by Home and Whitaker. PDF.
Also on p. 361 of ref. [3], he says, “the Statistical Interpretation considers a particle to always be at some position in space, each position being realised with relative frequency [itex]\psi(\mathbf{r})^2[/itex] in an ensemble of similarly prepared experiments”. Later [3, p. 379] he states, “there is no conflict with quantum theory in thinking of a particle as having definite (but, in general, unknown) values of both position and momentum”.Reference [3] is of course Ballentine's article. What does this have to do with Bell? I don't have a rigorous argument, because I don't even know if there are Bell inequalities for position and momentum like the ones we've all seen for spin component operators, so I can only argue by analogy. What Ballentine said in 1970 about position and momentum can definitely not be said about spin components, because that statement would lead directly to a Bell inequality called the CHSH inequality (see pages 215, 216 in Isham's book for a derivation), which is violated by QM and by nature. This makes me believe that Ballentine's statements about position and momentum can't be correct either. I suspect that Ballentine didn't know Bell's theorem (which was published in 1964) when he wrote the article in 1970, and that if he had, he wouldn't have said those things. Ensemble/Statistical: It doesn't. MWI: It does. "Shut up and calculate": I don't care. Since the question can't be answered by experiment, "shut up and calculate" is the only one of these "interpretations" that doesn't say anything unscientific. (If anyone is wondering how I define "describes" and "actually happens" in this context, the answer is that I don't. I consider them primitives, not terms that need to be defined. I don't think they can be defined in a way that improves on the situation we have if we take them as primitives). 


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